Based on this small post here, it got me thinking... The reputation(rep) with factions and what it "allows" the player to do could use improvements, but implementing such a system would likely need lots of work?

It would be great if the garbage, normal items and useful items from each faction could be taken, while impacting upon players Fame/Infamy(F/I) with that faction, the impact is based (from greater to lesser degree) on players current F/I with them.

For example going to Moiras shop and taking a bottlecap mine would initially cause hostility with Craterside Supply/Megaton, but once the player has a moderate Fame there, taking the mine would only reduce Fame (or increase Infamy? but not enough to cause hostility), and if the player has a high enough Fame in the faction, Moira could not mind if the player takes the item, or the negative impact (F/I) would instead be minimal.

Ofc taking a Tin Can would be different (minimal impact and only if player Fame with faction is low, otherwise taking "trash" can be done at will), so items would have a "score" (minimum/medium/high) based on the impact they cause on F/I within that faction.

It is scarcely based on the principle that the wasteland has its own eyes and ears, and everything the player do has a consequence, instant or over time, whether there are witnesses or not.

Player gets a "Karma based" bonus or penalty to F/I when interacting with a faction during certain dialogs (non-repeatable ones), for example upon entering Megaton and answering to Lucas Sims, player current Karma (which determines overall reputation through the wasteland) is checked and since Megaton is a good/lawful place, good karma increases Fame while bad increases Infamy.

Aside from some dialogs here and there, karma does (mostly?) nothing, F/I has to be built through faction specific dialogue/tasks/quests. But Karma reflects how "general wasteland factionLESS people" such as caravaners or wastelanders will treat the player. This makes for interesting cases where the player could be a criminal for the wasteland, but a hero to a faction.

Building Fame with each faction could be harder, but provide more benefits to it, such as being able to "take items" or "trespass property" from that faction, without it being considered an aggressive action (obviously there are restrictions when applicable, to not break some plots). Actions of this type may still increase Infamy with the faction, but impact tends to be less and less based on how high players Fame currently is with them.
(Also not confuse taking items with the crouch/steal from NPCs, being caught stealing is as bad as it ever was, should increase Infamy by a large margin or even cause hostility.)

Another point of having a high Fame with a faction are specific benefits, up to imagination and creativity when expanding how these work. For example at 50% Fame in Megaton the player receives the house, at 60 he can ask to check Moira/Doctor/Brothers/etc computers and be granted access (pass speech challenge for each?), at 80 gets a minor discount in healing/cure rad/addictions with Doc Church. Reaching 100 (max?) with Megaton causes the player to be entrusted with a key to the armory.

This could also be reversed when the player gets high Infamy with a faction, creating extra troubles such as slavers or talon sending elite hunting parties after the player, or for example if player is already disliked in Megaton then raids the armory there, on top of going hostile the faction even forms a group with Lucas Sims + Billy + Jericho + Deputy Weld + Craterside Guard to try and ambush player in the wasteland.

Increasing Fame should take longer than reducing it. For example, upon 1st talk to Lucas Sims player is very nice to him, gets initial Fame of 15 in Megaton, this will slowly climb to 25 (a +10) over the course of 3 days, to reflect the time it took for Sims to gossip around spreading a good word about the player. On the other hand, if the player takes an item, it will affect F/I almost immediately (but won't stop the previous +10 bonus from filling up, unless the faction goes hostile).

Well, a system like that would probably require a large mod to adjust each faction/place?? Maybe a mod group effort where each person takes a place/faction. IMO it would make for such a lively and immersive wasteland! DC specially :)